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Eternal Flame Indestructible LED Lantern 


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Eternal Flame Indestructible 

LED Lantern 

Written By: Steve Hoefer 


• 3/8" drill bit M) 

• Drill press (1) 

• Drill vised) 

• Pliers (1) 

• Wire cutter d) 


• Thread sealing tape (1) 


• Electrical Tape (1) 

Binder clip (1) 
W wide or smaller 

• Coin cell battery (1) 

• LEDd) 


10mm, diffused lens anv color 

Pipefittinqs fn 

parts #447-010 and #449-010. 

pvcfittinasonline. com 


If you're like me, you're the bane of hardware store employees. I wander through the whole 
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Eternal Flame Indestructible LED Lantern 

place picking up everything, looking at possibilities more than parts. Can they help me find 
anything? "No thanks," I answer. What am I working on? "I don't know yet," I say. They 
move on, keeping a suspicious eye on me. 

Some things just seem useful, even if I can't think of how at the moment. One time I found 
matched pairs of PVC caps and plugs that fit together into little airtight pods of various 
sizes. For what, I didn't know until I wanted a way to float lit LEDs down a stream. 

The result: simple, rugged, floating LED lanterns that glow for days. They've survived being 
submerged for a week, frozen, and laundered in the washing machine. I even hit one with the 
lawn mower, and it still works. When they get dirty, just hose them off. 

Step 1 — Drill the hole for the LED. 

• Drill a hole in the top center of the cap using a 3/8" bit; it's just under 10mm and will make 
a watertight fit for the LED. 

• Use a drill vise to prevent kickback. To protect the cap from scratches, you can line the 
vise jaws with tape or cut a V in 2 pieces of scrap wood. 

• In the original article, author Steve Hoefer was pictured wearing gloves while using 
a drill press, which is a safety hazard. "Gloves are a no-no around rotating tools," 
Steve admits. Thanks to reader Tim Kemp for pointing out the error. 


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Eternal Flame Indestructible LED Lantern 

Step 2 — Prepare the LED. 

• Cut about V2" (13mm) off the end of each LED lead, so they'll fit easily inside the lantern. 
Use pliers to bend a small dogleg in the longer, anode (+) pin. This will keep the shorter, 
cathode (-) pin from accidentally shorting out the side of the battery. 

• Finally, for watertightness, put a single wrap of thread sealing tape around the base of the 

Step 3 — Insert the LED. 

• Place the LED in the pliers so that 
their blunt nose is flush against the 
bottom of the LED lens. This will let 
you push the LED firmly without 
mangling it. Push the LED through 
the cap from the inside until it's 
flush with the inside of the cap. If 
the fit is too tight using just your 
hands, use the open end of the plug 
as a backstop and gently tap the 
handle of the pliers with a rubber 

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Eternal Flame Indestructible LED Lantern 

Step 4 — Insulate the binder clip. 

• The enamel coating on the binder 
clips can insulate but tends to chip. 
To avoid shorting out your LED, 
apply electrical tape inside the clip. 
The pliers can help hold it open. 

Step 5 — Power on. 

• Slide the coin cell battery between the 2 LED leads, with the smooth (positive) side against 
the longer lead. The LED should light up. Clip the binder clip over the top to hold the leads 
securely to the LED. 

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Eternal Flame Indestructible LED Lantern 

Step 6 — Close it up. 

• Wrap the top edge of the plug once 
with a strip of sealing tape to keep 
any water out. Then squeeze the 
plug into the cap. 

• If you plan to use the lantern in 
water, make it easier to retrieve by 
drilling a small hole in the edge of 
the plug and tying in some fishing 
line. The lanterns tend to float 
upright; but if you want them to 
sink, add some fishing weights or 
steel nuts before final assembly. 

• When the battery or LED has 
reached the end of its useful life, a 
firm twist will loosen the assembly 
for replacement. 

Step 7 — Illuminate. 

• Use your LED lanterns anywhere you'd like some durable illumination. They're better in 
large numbers, and you can get interesting effects by using flickering or color-changing 

• I've used them to light up a yard party and to mark the trail for night hiking. I've floated 
them downstream, frozen them in ice, even used them as ammo in a pneumatic cannon. 
What you can use them for is limited only by your imagination. 

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Eternal Flame Indestructible LED Lantern 

This document was last generated on 2012-11-17 09:55:52 PM. 

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